Improvements in or relating to protective arrangements for use with rotating parts

868,197. Machinery guards. ROLLS-ROYCE Ltd. Sept. 10, 1957 [Sept. 28, 1956], No. 29765/56. Class 80 (4). [Also in Group XXVI] To prevent damage by fragments resulting from the breaking of a part which is rotating at high speed, the part is surrounded by a stationary guard comprising a web of closely woven or braided wire or metal strip which may have a sheet metal liner. As applied to a gas turbine wherein a casing 10, Fig. 2, encloses turbine blades (not shown), the guard 15 surrounds the casing 10 and comprises a sheet metal liner 17, Fig. 3, supporting several convolutions of a long web 16, the web comprising a flattened tube of braided steel or aluminium wires. In order to support the coiled web 16 the liner 17 carries a number of flanged bars 18 in hooked engagement with a series of overlapping plates 24 on which the web 16 is coiled, one of the plates 24 carrying a flanged bar 25 on which is hooked a fitting 26 secured to one end of the web. The other end of the web has a fitting 27 co-operating with a ribbed bar 28 on a detachable outer wall 22 of the guard. One end of the wall 22 slidingly engages below a flange on an end wall 20 secured to the liner 17, the liner' being supported by a ring 19 engaging a slot in a fixed flange 31. The other end of the wall 22 has a flange 23a bolted between a flange on the liner 17 and a fixed flange 34. Reinforcing metal plates may be intercalated between the convolutions of the web 16. The guard 15 forms part of a cooling air jacket surrounding the turbine casing 10, said jacket also including a wall 30 and an outlet manifold 33.